To get a proper translation, you need to specify which Celtic language you're interested in. For example:
* Irish: `beag` (pronounced roughly beg) is a common word for "little" or "small."
* Scottish Gaelic: `beag` (pronounced similarly) also means "little" or "small."
* Welsh: `bach` (pronounced roughly bach) is a common word for "little" or "small."
And so on for other Celtic languages. Each will have its own nuances and variations depending on the context.